Effects of chronic food stress on morphometry and expression of nuclear organizing regions in the adult rats hippocampus Chronic food stress on morphometry and expression of agnor in the rats hippocampus / Efeitos do estresse alimentar crônico na morfometria e expressão das regiões de organização nuclear nos ratos adultos hipocampo Testemunho crônico de alimentação sobre morfometria e expressão do agnor no hippocampus das taxas

Abstract

The aim of this study was to verify the immediate and late effects of chronic food stress on the expression of Nuclear Organizing Regions (NORs) in hippocampal neurons. Twenty Wistar rats were separated into two groups: test (n = 10) and control (n = 10). Food stress started from the 60th day of life and lasted for a month. After this time the animals were anesthetized, euthanized and had their hippocampus dissected. The obtained hippocampus were histologically processed, stained by the HE technique for morphological description and by the AgNOR technique for NOR analysis. From each image the total number of neurons, the number of neurons with NOR in Dispersion (NND), the total number of NORs (NNOR), and then performed a ratio of NNOR by the total number of neurons to obtain the number Of NOR by neuron (NNN). Of the analyzed variants, the number of neurons was higher (p <0.001) in the stressed group (41.98 ± 17), when compared with the control group (33.57 ± 14). In addition, NND was also higher in the stressed group (4.523 ± 4.04) than the control group (1.4 ± 2.20) with p <0.001. Thus, we have that chronic food stress increases the number of granular neurons in the hippocampus in rats as well as increases the number of NOR in dispersion.